The commentary is certainly worth reading - if you happen to have Nature access - although it will be enraging for some. As others have already noted, Goldstein uses the commentary as a platform for propounding his views on the genetic basis of common diseases. However, as someone without a dog in the rare vs common variant fight, Goldstein's insinuations here didn't bother me too much. What did bug me is towards the end of the piece, when Goldstein brings out a tired claim about the potential dangers of prenatal screening:

One potential problem with this is that numerous genetic risk factors will have diverse and unexpected effects — sometimes causing disease, sometimes being harmless and sometimes perhaps being associated with behaviours or characteristics that society deems positive. [...] Wholesale elimination of variants associated with disease could end up influencing unexpected traits — increasing the vulnerability of populations to infectious diseases, for instance, or depleting people's creativity.

This argument - that removing serious disease mutations from the population will inadvertently deprive society of artistic ability, sparkling conversational wit or some other allegedly positive trait - is all too common, and tends to be followed by:

1. People nodding their heads very seriously;2. "Take that physicist," the head-nodders say, "you know, the one in the wheelchair. If there was prenatal screening for whatever he has back when he was conceived he would never have thought of, you know, whatever it is he's famous for."3. More nodding of heads and serious expressions, as though this were a profound and troubling argument against prenatal screening for diseases.

However, for this argument to provide a serious moral case against prenatal testing, two things must be true:

1. Disease mutations must in fact be significantly correlated with some positive trait; and2. The benefits to the world of these positive traits must outweigh the suffering and death caused by genetic disease.

The first is known to be true only in the limited setting (noted by Goldstein) of resistance to infection - for instance, the mutation that causes sickle cell anaemia also protects against malaria - but this seems likely to be an exception rather than a rule. It's also unclear that this constitutes a moral argument against prenatal screening: the way to reduce the suffering caused by malaria is to work towards eliminating Plasmodium falciparum, not to deliberately allow a disease-causing mutation to continue to wreak havoc. And in any case, sensible screening could identify embryos at risk of sickle cell anemia (which only affects people carrying two copies of the mutation) without eliminating individuals resistant to malaria (who need only carry one copy).

Also, remember that Goldstein is talking here about very rare disease mutations, often affecting a single extended family; these aren't like the sickle cell allele, which shows evidence for having been increased in frequency in malaria-endemic regions through positive natural selection.

The idea of a yin-yang balance of mutational effects is aesthetically pleasing in its symmetry, explaining its visceral appeal to the head-nodders mentioned above, but there's no evidence that it represents a general principle of nature, and no compelling biological or evolutionary reason to expect gene-breaking mutations as a class to produce compensatory boosts to human traits. There are many great physicists who are not, in fact, confined to a wheelchair; there are many great artists who live without the burden of clinical depression. If screening for amyotrophic lateral sclerosis had been available in 1942 Stephen Hawking would probably never have been born - instead, another human being would have entered the world, able to choose his path in life without the suffering of a degenerative disease; and many highly successful physicists would still be working away.

But nonetheless, let's accept that there may be some correlation between some disease mutations and some positive human traits. The question then is: should this correlation prevent us from giving parents the option of choosing not to have children who carry a severe disease mutation? Is the Jewish community wrong, for instance, to encourage pre-conception carrier testing to reduce the incidence of Tay-Sachs disease, lest it turn out that (as some have controversially argued) the disease allele is in fact associated with some positive trait?

To his credit, Goldstein doesn't actually make this argument: he says he is "supportive of the rights of parents to choose," even in controversial cases such as the APOE variant associated with increased risk of late-onset Alzheimer's disease. Still, his mention of this yin-yang argument as something that may have serious merit - something that we, as a society, must ensure we discuss at length while adopting suitably concerned expressions - is unfortunate.

Within the next few years we will have the tools to allow every parent in the industrialised world to make a fully informed decision about whether they wish to have a child who will suffer from a serious, untreatable disease. There will, indeed, be serious consequences as this technology becomes widely adopted (as it will inevitably be). For instance, parents who choose not to use this technology and have a severely disabled child as a result will have to live with an extra new burden of guilt, and likely face additional social ostracism. As the number of children affected with severe genetic diseases decreases there will likely be decreased funding available for the treatment and care of disease sufferers. As Goldstein correctly notes, prospective parents will face complex choices: for those undergoing IVF, for instance, a finite number of embryos to implant will often mean trading one uncertain disease risk off against another. And there will inevitably be a drift towards embryo selection based on non-disease traits, with unpredictable (although, I suspect, manageable) consequences.

These are all perfectly valid concerns that need to be addressed. But the idea that prenatal screening will rob society of some crucial positive trait is nothing more than a distraction, and we should save our serious expressions and worried head-nodding for more concrete concerns.